triceps

A large three-headed muscle running along the back of the upper arm and serving to extend the forearm.

Three-headed; tricipital; specifically, in anatomy, noting certain muscles which arise by three heads.

A tricipital or three-headed muscle, which has a triple origin and proceeds to a single insertion; especially, such a muscle of the fore or hind limb, expressly named as in the following phrases.

A muscle having three heads; specif., the great extensor of the forearm, arising by three heads and inserted into the olecranon at the elbow.

Any muscle having three heads.

Specifically, the triceps brachii.

any skeletal muscle having three origins (but especially the triceps brachii)